Isotopes

How many neutrons would Fe-56 have?

• 56
• 26
• 30
• 33

If an atom of oxygen has a charge of -2, how many electrons does the atom have?

• 18
• 6
• 8
• 10

How many neutrons does the isotope below have?     ⁸⁹ ₃₆Kr

• 53
• 36
• 89
• 125

Tags

NGSS.HS-PS1-8

If X is the symbol for an element, which of the following two symbols represent    isotopes of the same element?     I. ⁷⁷₃₅X  II. ⁷⁷₃₃X  III. ⁸¹₃₇X  IV. ⁸¹₃₅ X

• I and II
• III and IV
• I and IV
• I and III

Tags

NGSS.HS-PS1-8

Four isotopes of lead include lead-204, lead-206, lead-207, and lead-208.  The average atomic mass of lead is 207.2.  Which isotope of lead is likely to be the most abundant.

• 204
• 206
• 207
• 208

What is the name of the pictured isotope?

• Copper-29
• Copper-63
• Copper-34
• CopperWopperHopperBopper

Tags

NGSS.HS-PS1-8

24.1% of all the isotopes of a an element have a mass of 75.23 amu, 48.7% have a mass of 74.61 amu, and 27.2% have a mass of 75.20 amu.
What is the average mass of this element?

• 74.92 amu
• 24.97 amu
• 75.01 amu
• 74.51 amu

Calcium has three different isotopes. One has a mass of 35.00 amu; another has a mass of 41.00 amu; and another has a mass of 40.00 amu. Which isotope is the most abundant of the three?

• 40.00 amu
• 41.00 amu
• 35.00 amu
• impossible to tell

An isotope has three forms.  30% have a mass of 4 amu, 20% have a mass of 5 amu and 50% have a mass of 3 amu.  Average atomic mass will be closest to

• 2 amu
• 3 amu
• 4 amu
• 5 amu

How many neutrons are in the isotope pictured above?

• 29

• 34

• 63

• 92

Tags

NGSS.HS-PS1-8